1. Field of the Invention
The present invention relates to a connector contact capable of coping with a decrease in pitch and shortening the time required for assembly.
2. Description of the Prior Art
As an example of a conventional connector contact, a so-called tulip-shaped contact 100 with the structure shown in FIG. 1 is available. The contact 100 is comprised of a main body portion 103 bent to have a U-shaped section and having a base plate portion 101 and a pair of parallel upright plate portions 102 standing vertically from the two edges of the base plate portion 101, elastic pieces 104 extending like beams in the same direction from the respective upright plate portions 102 of the main body portion 103, and contact portions 105 formed at the distal ends of the elastic pieces 104. When a male contact 106 is pushed between the contact portions 105, the elastic pieces 104 elastically deform, as they are forced apart by the male contact 106, to separate the contact portions 105 apart from each other so as to receive the inserted male contact 106 between them. Simultaneously, the contact portions 105 are urged against the male contact 106 by the elastic forces of the elastic pieces 104, so that they come into reliable contact with the male contact 106.
Assume that a connector is to be fabricated by building this contact 100 into a connector housing 107 shown in FIG. 3. First, a flat plate member is punched to form a flat plate-like blank in which a plurality of contact forming portions 100A each shown in FIG. 2 are lined at the equal pitch in a common carrier 110 shown in FIG. 3. The contact portions 105 are formed at the elastic pieces 104 of each contact forming portion 100A of this blank so as to make the elastic pieces 104 serve as contacts, and after that the contact forming portion 100A is bent at bending lines indicated by alternate long and short dashed lines in FIG. 2 to have the shape of the contact 100. As shown in FIG. 3, the plurality of contacts 100 held by the carrier 110 in this manner are inserted in holes 111 in the connector housing 107 simultaneously, and then the individual contacts 100 are separated by cutting.
In recent years, a pitch W0 shown in FIG. 3, with which the contacts 100 are disposed in the connector, is greatly narrowed. The mainstream pitch W0 is 2.0 mm, and a connector with a pitch of about 1.5 mm is also under development. In order to cope with this decrease in pitch, the pitch with which the contact forming portions 100A, serving as a developing form of the contacts 100, are to be disposed must also be narrowed. With the contact 100 with the shape described above, when the main body portion 103 with the U-shaped section is developed, its width W2 shown in FIG. 2 is large, and a decrease in pitch is accordingly limited. More specifically, with the contact 100 with the shape described above, after the male contact 106 is fitted in it, it clamps the male contact 106 with contact forces, thereby exhibiting its connecting function. In order to clamp the male contact 106 in this manner, the main body portion 103 that supports the proximal portions of the elastic pieces 104 so that they oppose each other must be bent into a U-shape, and the U-shaped main body portion 103 must have such a size that it can sufficiently receive the male contact 106 (more specifically, when the male contact has a width of 0.5 mm, the main body portion 103 must have an inner width of about 1.5 mm). Consequently, the width W2 described above increases undesirably.
For this reason, with these contacts 100, a pitch W2xe2x80x2 (shown in FIG. 3) of the contact forming portions 100A in the blank, which is inevitably larger than the width W2 obtained by developing each main body portion 103, must be twice the pitch W0 with which the holes 111 are formed in the connector housing 107, the plurality of contacts 100 held by the carrier 110 must be inserted in every second holes 111 of the connector housing 107, and similarly the plurality of contacts 100 held by another carrier 110 must be inserted in the remaining every second holes 111. Otherwise, a decrease in pitch cannot be coped with (more specifically W2xe2x89xa6W2xe2x80x2=2xc3x97W0).
Then, however, two steps are needed to dispose the contacts 100, and consequently, the time required for assembly increases undesirably. If the width W2 is large, the amount of material necessary for forming each contact 100 increases, leading to an increase in cost.
As another example of the connector contact, a so-called fork-shaped contact 120 with the structure shown in FIG. 4 is available. This contact 120 has a flat plate-like shape as a whole, and is comprised of a main body portion 121, a pair of elastic pieces 122 extending like beams from the two sides of the main body portion 121, and contact portions 123 respectively formed at the distal ends of the elastic pieces 122. When a male contact is pushed between the contact portions 123, the elastic pieces 122 elastically deform, as they are forced apart by the male contact, to separate the contact portions 123 apart from each other so as to receive the inserted male contact between them. Simultaneously, the contact portions 123 are urged against the male contact by the elastic forces of the elastic pieces 122, so that they come into contact with the male contact.
Assume that a connector is to be fabricated by building this contact 120 in a connector housing. First, a flat plate member is punched to form a flat plate-like blank in which a plurality of contacts 120 each with the shape described above are lined at the equal pitch, and after that the plurality of contacts 120 are inserted in the holes in the connector housing simultaneously.
With the contacts 120, since the main body portions 121 need not be formed to have a U-shaped section like that of the main body portion 103, the width of the contact 120 can be decreased, and accordingly the pitch with which the contacts are disposed in the blank can also be decreased. Even when coping with a decrease in pitch with which the contacts are to be disposed, the contacts 120 can be inserted in the adjacent holes of the connector housing simultaneously with one blank. As a result, the time required for assembly can be shortened, and the amount of material necessary for forming each contact 120 decreases, leading to a decrease in cost.
In the contact 120 with this structure, since those surfaces of its contact portions 123 which come into contact with a male contact 106 are low-smoothness sheared sections formed by punching, contact error undesirably occurs.
Since the contact portions 123 and main body portion 121 are located on the same plane, the male contact cannot have a sufficiently large insertion length due to the problem of interference with the main body portion 121, and the male contact can be sometimes disengaged easily during use.
Japanese Unexamined Patent Publication No. 7-326417 discloses a contact that can solve the problem on contact error of the contact 120 described above. This contact is a fork-shaped contact comprised of a main body portion, a pair of elastic pieces extending like beams in the same direction from two sides of the main body portion, and contact portions respectively formed at the distal ends of the elastic pieces. The elastic pieces are twisted midway, so those portions of the contact portions which come into contact with a male contact form high-smoothness rolled surfaces.
Even in this contact, since the contact portions and the main body portion are located on the same plane, the male contact cannot have a sufficiently large insertion length due to the problem of interference with the main body portion, and the male contact can be sometimes disengaged easily during use.
The present invention has been made in view of the above situations in the prior art, and has as its object to provide connector contact which can cope with a decrease in pitch, shorten the time required for assembly, decrease the cost, come into contact with a male contact with high-smoothness rolled surfaces, and assure a sufficiently large insertion length of the male contact.
In order to achieve the above object, according to the first main aspect of the present invention, there is provided a connector contact having a main body portion, a pair of elastic pieces extending like beams on the same side from two sides of the main body portion, and contact portions respectively formed in distal ends of the elastic pieces, to come into contact with a male contact inserted between the contact portions, wherein the pair of elastic pieces have, at the distal ends thereof, protrusions at which the contact portions are to be arranged and each of which projects in a lateral direction opposite to the other elastic piece, and the pair of elastic pieces are deformed by twisting or bending, so that the contact portions oppose each other.
In this manner, the pair of elastic pieces extending like beams on the same side from two sides of the main body portion have, at their distal ends, the protrusions at which the contact portions are to be arranged and each of which projects in the lateral direction opposite to the other elastic piece, and the pair of elastic pieces are deformed by twisting or bending, so that the contact portions arranged on the protrusions oppose each other. Therefore, the main body portion need not be formed to have a C-shaped section, and the width of the contact can be decreased. Even when coping with a decrease in contact pitch of a connector housing, a plurality of contacts made from one blank and connected to each other can be inserted into adjacent holes of the connector housing simultaneously, so that the time required for assembly can be shortened, and the amount of material necessary for forming each contact can be decreased, thus achieving cost reduction.
The pair of elastic pieces are deformed by twisting or bending, so that their contact portions oppose each other. Accordingly, those portions of the contact portions with which the contact portions come into contact with the male contact can form high-smoothness rolled surfaces. Hence, the contact portions can come into contact with the male contact with the high-smoothness rolled surfaces.
The pair of elastic pieces have, at their respective distal ends, the protrusions at which the contact portions are to be arranged and each of which projects in the lateral direction opposite to the other elastic piece, and the pair of elastic pieces are deformed by twisting or bending, so that the contact portions oppose each other. Accordingly, the contact portions can be arranged at positions shifted from that of the main body portion. Hence, the male contact can have a sufficiently large insertion length.
According to one subsidiary aspect of the present invention, in the connector contact according to the first main aspect described above, the pair of elastic pieces are deformed by bending, so that the contact portions oppose each other.
In this manner, the pair of elastic pieces are deformed by bending, so that the contact portions oppose each other. Therefore, when compared to a case wherein the contact portions are made to oppose each other by deforming the pair of elastic pieces by twisting, the number of steps can be decreased, and the contact portions can have high precision.
According to the second subsidiary aspect of the present invention, in the connector contact according to the first subsidiary aspect described above, the pair of elastic pieces are deformed by bending at linear portions extending in the protrusions along an inserting direction of the male contact, so that the contact portions oppose each other.
In this manner, the pair of elastic pieces are deformed by bending at the linear portions extending in the protrusions along the inserting direction of the male contact, so that the contact portions oppose each other. Therefore, the punch and die of the press can have simple shapes. Accordingly, the manufacturing cost can be reduced.
According to the third subsidiary aspect of the present invention, in the connector contact according to the first subsidiary aspect described above, each of the pair of elastic pieces is deformed by bending at a first linear portion arranged closer than the protrusion of one elastic piece to the other elastic piece, and a second linear portion extending obliquely from the first linear portion on a side closer to the main body portion to an outer end of the elastic piece, so that the contact portions oppose each other.
In this manner, each of the pair of elastic pieces is deformed by bending at the first linear portion arranged closer than the protrusion of one elastic piece to the other elastic piece, and the second linear portion extending obliquely from the first linear portion on the side closer to the main body portion to the outer end of the elastic piece, so that the contact portions oppose each other. Therefore, slant portions can be formed at the proximal portions of the protrusions closer to the main body portion. The slant portions can accordingly prevent stress concentration at the proximal portions of the protrusions and can improve the strength.
As the strength is improved, when the male contact is inserted between the contact portions, the contact portions can be separated apart from each other without changing their postures, and consequently they can come into good contact with the male contact.
Since each of the elastic pieces is bent at the first linear portion arranged inner than its protrusion to extend along the inserting direction of the male contact, the distance between the two protrusions before bending can be further decreased while assuring the heights of the protrusions after bending. This can cope with a further decrease in contact pitch.
According to the fourth subsidiary aspect of the present invention, in the connector contact according to any one of the aspects described above, the protrusions on the sides closer to the main body portion have slant portions which slant such that the closer to the main body portion, the smaller their projecting amounts.
In this manner, the protrusions on the sides closer to the main body portion have the slant portions which slant such that the closer to the main body portion, the smaller their projecting amounts. Thus, these slant portions can prevent stress concentration at the proximal portions of the protrusions and can improve the strength.
As the strength is improved, when the male contact is inserted between the contact portions, the contact portions can be separated apart from each other without changing their postures, and consequently they can come into good contact with the male contact.
According to the second main aspect of the present invention, there is provided a method of manufacturing a connector contact which has a main body portion and a pair of elastic pieces extending like beams on the same side from two sides of the main body portion, and in which distal ends of the pair of elastic pieces have protrusions at which contact portions are to be arranged and each of which projects in a lateral direction opposite to the other elastic piece, the contact portions being made to oppose each other by deforming the pair of elastic pieces by bending, comprising the steps of deforming the distal ends of the main body portion, at which the pair of elastic pieces are to be formed, by bending so that the contact portions oppose each other, and punching an intermediate portion of the distal end of the main body portion in a longitudinal direction into a predetermined length to separately form the pair of elastic pieces.
In this manner, after the distal end of the main body portion is deformed by bending, the intermediate portion of the distal end of the main body portion is punched to separately form the pair of elastic pieces. Therefore, bending deformation can be performed while the strength of the distal end of the main body portion is maintained, so that the precision of bending deformation can be improved greatly.
The above and many other objects, features and advantages of the present invention will become manifest to those skilled in the art upon making reference to the following detailed description and accompanying drawings in which preferred embodiments incorporating the principle of the present invention are shown by way of illustrative examples.